javascript当中鼠标有截断现象（进入上层元素，没进入下层元素）的解决方案
例 12.2 onmousemove事件
马克-to-win：本例子中两个元素，不是嵌套重合元素（参见第10节），所以事件肯定先进入上层元素，所以鼠标有截断现象（进入上层元素，没进入下层元素）解决方案见下面一个例子。
<head>
<meta http-equiv="content-type" content="text/html; charset=utf-8"/>
<div id="divtest" style="position:absolute;width:300px;height:300px;background:#999;">
</div>
<div id="img" style=" z-index:1; position:absolute; width:0px; height:0px; left:0px;top:0px"><img src="1.jpg" /></div>
<script>
var car = document.getElementById("img");
function move(event)
{
var event = event || window.event;
car.style.left = event.clientX ;
car.style.top = event.clientY;
}
document.getElementById("divtest").οnmοusemοve=move;
</script>
例 12.2_b
马克-to-win：本例通过事件派发解决上个例子的问题。
<head>
<meta http-equiv="content-type" content="text/html; charset=utf-8"/>
<div id="divtest" style="position:absolute;width:300px;height:300px;background:#999;">
</div>
<div id="img" style=" z-index:1; position:absolute; width:0px; height:0px; left:0px;top:0px"><img src="1.jpg" /></div>
<script>
var car = document.getElementById("img");
var myEventx;
var myEventy;
function move(event)
{
var event = event || window.event;
// alert("move");
/*你会发现，除正常以外，当dispatchEvent时，event.clientX总为undefined，所以提前就得myEventx=event.clientX;*/
// alert("ok"+"event.clientX is "+event.clientX);
if(event.clientX==undefined) event.clientX=myEventx;
if(event.clientY==undefined) event.clientY=myEventy;
car.style.left = event.clientX ;
car.style.top = event.clientY;
}
function move1(event)
{
var t = document.getElementById('divtest')
var event = event || window.event;
// alert("ok11111"+"event.clientX is "+event.clientX);
/*下面两句话是dispatchEvent时才用到。*/
{
var evt = document.createEvent('HTMLEvents');
evt.initEvent('mousemove', true, true);
t.dispatchEvent(evt);
}
}
document.getElementById("divtest").οnmοusemοve=move;
document.getElementById("img").οnmοusemοve=move1;
</script>
更多内容请见原文，文章转载自：https://blog.csdn.net/qq_43650923/article/details/102988342
